When a nerve is either not working, the muscles in the face do not receive the signals needed to function, which leads to paralysis of parts of the face and affect the movement of the eyes or mouth.

Sometimes only the lower half of the face is affected, sometimes one whole side of the face is affected and in some cases both sides of the face are affected.

Branches of nerves supply the muscles which are used for facial expression, as well as tears, saliva production and taste.

The most commonly known cause of facial paralysis is Bell’s palsy, which is based by a viral infection, as is Ramsey Hunt syndrome, there are actually many different causes of facial palsy, and treatment and prognosis vary greatly depending on the cause. Some of the main causes of facial palsy are listed below:

Causes can also include surgical issues, bacteria such as Lyme disease or following a middle ear infection, neurological conditions, a traumatic injury such as a fracture, or a trauma during birth, such as damaged caused by forceps and can also be a congenital condition, where there is abnormal development of the facial nerves or muscle in the womb.

There are different levels of nerve injury, setting out how long recovery can take or if it permanent.